TY  - JOUR
AU  - Trump, B. A.
AU  - Koohpayeh, S. M.
AU  - Livi, K. J. T.
AU  - Wen, J.-J.
AU  - Arpino, K. E.
AU  - Ramasse, Q. M.
AU  - Brydson, R.
AU  - Feygenson, M.
AU  - Takeda, H.
AU  - Takigawa, M.
AU  - Kimura, K.
AU  - Nakatsuji, S.
AU  - Broholm, C. L.
AU  - McQueen, T. M.
TI  - Universal geometric frustration in pyrochlores
JO  - Nature Communications
VL  - 9
IS  - 1
SN  - 2041-1723
CY  - [London]
PB  - Nature Publishing Group UK
M1  - FZJ-2019-00738
SP  - 2619
PY  - 2018
AB  - Materials with the pyrochlore/fluorite structure have diverse technological applications, from magnetism to nuclear waste disposal. Here we report the observation of structural instability present in the pyrochlores A2Zr2O6Oʹ (A = Pr, La) and Yb2Ti2O6Oʹ, that exists despite ideal stoichiometry, ideal cation-ordering, the absence of lone pair effects, and a lack of magnetic order. Though these materials appear to have good long-range order, local structure probes find displacements, of the order of 0.01 nm, within the pyrochlore framework. The pattern of displacements of the A2Oʹ sublattice mimics the entropically-driven fluxional motions characteristic of and well-known in the silica mineral β-cristobalite. The universality of such displacements within the pyrochlore structure adds to the known structural diversity and explains the extreme sensitivity to composition found in quantum spin ices and the lack of ferroelectric behavior in pyrochlores.
LB  - PUB:(DE-HGF)16
C6  - pmid:29976983
UR  - <Go to ISI:>//WOS:000437417600006
DO  - DOI:10.1038/s41467-018-05033-7
UR  - https://juser.fz-juelich.de/record/859922
ER  -